1. Field of the Invention
The present invention relates to a photographic film developing apparatus for developing a color photographic film.
2. Description of the Prior Art
Due to a reduction in the size of photographic film developing apparatus and photographic printing apparatus associated with their price reduction, the number of small-scale photographic processing shops (or so-called xe2x80x9cminilabsxe2x80x9d) has rapidly increased in recent years. Having such apparatus at their shops, these minilabs develop films and produce photographic prints very quickly. Also becoming common today is the use of digital cameras, in place of conventional film cameras. As a result, the number of films developed at a single small-scale photographic processing shop is decreasing these days and this tendency is supposed to continue.
In a conventional photographic film developing apparatus, the film is developed as it is transferred through a series of tanks filled with a developer solution, a bleaching solution, a fixer solution and a stabilizer solution. As the number of films developed at a photographic processing shop is decreasing as stated above, these solutions are replaced less frequently. While the individual solutions deteriorate as the number of processed films increases, they also deteriorate with the lapse of time due to evaporation of water, for example. It is likely that the quality of images on negative films developed at a small-scale photographic processing shop which processes a small number of films varies over the course of time.
In addition, maintenance cost of a less frequently used photographic film developing apparatus and cost of a shop space occupied by the apparatus impose an economic burden on the small-scale photographic processing shop where the number of processed films is small. Such economic burden would eventually drive the shop into a difficult financial status.
One previous approach to the solution of this problem is a photographic film development method proposed in Japanese Unexamined Patent Publication No. S62-92957, for example, in which appropriate amounts of individual solutions are directly sprayed or applied to an emulsion side of a photographic film. Since this film development method (hereinafter referred to as the direct application development method) utilizes unused processing solutions each time the film is developed, it is possible to produce images of a stable quality on the developed negative film. Furthermore, the direct application development method facilitates maintenance of a photographic film developing apparatus and helps reduce its overall physical size, because there is no longer the need for solution tanks.
It is known that chemical reaction in each process of photographic film development is controlled by the temperature of a processing solution and reaction time in the processing solution. For this reason, each processing solution is controlled to a specific temperature (e.g., 38xc2x0) as it is applied to the emulsion side of the photographic film regardless of seasons. Since the photographic film is normally stored at room temperature just until it is developed, however, its temperature varies from season to season.
In the conventional photographic film developing apparatus in which a photographic film is passed through a series of tanks filled with the processing solutions, the individual processing solutions have large thermal capacities and the tanks are provided with heaters for regulating the temperature of the solutions. The conventional photographic film developing apparatus thus constructed can maintain a stable quality in performing film development operation regardless of the temperature of the photographic film.
The photographic film developing apparatus employing the aforementioned direct application development method applies as small amounts of processing solutions as possible to the emulsion side of the photographic film, because the individual solutions are disposed of after use. Thus, the solutions used in the direct application development method have small thermal capacities and this poses a problem that the quality of images developed on the film is susceptible to the influence of the film temperature, resulting in seasonal variations in overall quality of the film development operation. One approach to the solution of this problem would be to store the photographic film in an atmosphere of an intended processing temperature for a specific period of time so that the entire film reaches a specific temperature before it is subjected to the development operation. However, this film preheating process takes time and, for a small-scale photographic processing shop which trades on quickness, causes a loss of competitiveness against other shops of the same scale.
In light of the aforementioned problems of the prior art, it is an object of the invention to provide a photographic film developing apparatus which can maintain a photographic film and processing solutions at a specific temperature while performing film development operation by directly applying the processing solutions to an emulsion side of the photographic film.
According to the invention, a photographic film developing apparatus for developing a photographic film by directly spraying or applying a processing solution to an emulsion side of the photographic film while it is being transferred at a specific speed comprises a transfer belt which comes into contact with a non-emulsion side of the photographic film when transferring it in a particular direction, and a heater for heating a contact surface of the transfer belt which comes into contact with the non-emulsion side of the photographic film to a specific temperature.
In this construction, the photographic film is heated from its non-emulsion side by the heater through the transfer belt during development operation, so that it is possible to maintain the entire photographic film and the processing solution sprayed or applied to the emulsion side of the photographic film generally at a specified temperature.